This invention relates to an actuating mechanism for simultaneously adjusting the optical powers of each of the two lens units in a pair of variable focus spectacles. The invention is described in relation to lens units of the general type disclosed in U.S. Pat. No. 5,138,494 (embodiment of FIG. 9 thereof), U.S. Pat. No. 5,371,629, and U.S. Pat. No. 5,688,620. The disclosures of all of said patents are relevant hereto, and are accordingly incorporated herein by reference.
Variable focus spectacles inherently include two lens units; it is accordingly desirable that an actuation means be provided to simultaneously control the optical powers of both. The present invention is intended to provide such a means.